immutable Animation{P<:PlottingObject}
  plt::P
  dir::ASCIIString
  frames::Vector{ASCIIString}
end

function Animation(plt::PlottingObject)
  Animation(plt, mktempdir(), ASCIIString[])
end
Animation() = Animation(current())

function frame(anim::Animation)
  i = length(anim.frames) + 1
  filename = @sprintf("%06d.png", i)
  png(anim.plt, joinpath(anim.dir, filename))
  push!(anim.frames, filename)
end


# -----------------------------------------------

"Wraps the location of an animated gif so that it can be displayed"
immutable AnimatedGif
  filename::ASCIIString
end

function gif(anim::Animation, fn::@compat(AbstractString) = "tmp.gif"; fps::Integer = 20)
  fn = abspath(fn)

  try
    
    # high quality
    speed = round(Int, 100 / fps)
    run(`convert -delay $speed -loop 0 $(anim.dir)/*.png $fn`)
  
  catch err
    warn("Tried to create gif using convert (ImageMagick), but got error: $err\nWill try ffmpeg, but it's lower quality...)")

    # low quality
    run(`ffmpeg -v 0 -framerate $fps -i $(anim.dir)/%06d.png -y $fn`)
    # run(`ffmpeg -v warning -i  "fps=$fps,scale=320:-1:flags=lanczos"`)
  end

  info("Saved animation to ", fn)
  AnimatedGif(fn)
end



# write out html to view the gif... note the rand call which is a hack so the image doesn't get cached
function Base.writemime(io::IO, ::MIME"text/html", agif::AnimatedGif)
  write(io, "<img src=\"$(relpath(agif.filename))?$(rand())>\" />")
end